Everyone has been in a situation while driving and experiencing the sound of emergency vehicles and then looking around and not knowing their location until it is too late to move aside. Also, everyone has experienced a time when they do not hear the approach of emergency vehicles or trains. Rail road crossings and school crossings are potential accident sites where drivers need to exercise caution. These situations can be very unsafe and dangerous to drivers, passengers, first responders, and pedestrians.
Emergency vehicles such as fire trucks, ambulances, and police cars frequently must reach an emergency situation as quickly as possible. Other vehicles such as school buses transport vulnerable passengers. To facilitate their travel from one point to another location they use warnings systems such as flashing lights and sirens. Even with these warnings systems many motorists are still surprised to see one of these emergency vehicles approaching them from behind, from either the left or the right, or from in front of them. The surprise may be caused because they couldn't hear the sirens due to listening to audio devices while driving. They may also have obstacles to their line of sight so that they cannot see the flashing lights of the approaching emergency vehicle.
Emergency vehicles, such as police cars, ambulances and fire engines, when in an emergency state, travel at a high rate of speed and, usually, do so through crowded streets and roadways. Laws require that other motor vehicles immediately give the right-of-way to the emergency vehicle. The driver of the motor vehicle then must be aware of the approach of the emergency vehicle within a suitable time to safely allow this right-of-way. Motorists become aware of an approaching emergency vehicle in an emergency status via flashing lights, sirens, and horns.
Emergency vehicles need to travel quickly and safely through traffic in order to get to a destination. Conventional emergency vehicles use either sirens or emergency lights, or both, in order to get to the destination quickly and safely. It is often the case that a driver who is on the same road or a nearby road as the emergency vehicle is not made aware of the emergency vehicle's presence. This may be the case when the driver has poor hearing, is listening to the car radio, is on his or her car phone, etc. When this occurs, it may result in a dangerous situation when the emergency vehicle approaches the unaware driver, which may result in the driver causing an accident with the emergency vehicle or with another nearby vehicle on the road.
Also, when an emergency vehicle comes to an intersection, it is important that all vehicles approaching the intersection in different directions are made aware of the approaching emergency vehicle. Again, some drivers may not be aware of the sirens and emergency lights of the emergency vehicle, and this may result in an accident occurring with the emergency vehicle and/or other vehicles at or near the intersection.
A substantial number of motorists are involved in accidents each year because they were not aware of an approaching emergency vehicle which has the right-of-way in all situations. In 1998, according the National Safety Council, there were over 32,000 accidents involving ambulances, fire trucks, police cars, and other emergency vehicles. It's a big problem with modern cars, vans, SUV's, and trucks featuring sound-proofing, 8-speaker 100-watt factory installed stereo sound systems, high volume air conditioning fans, cell phones, and the like. It is desirable that public safety be enhanced, yet not intruding on our comfort level that we have come to expect with modern vehicles.
There are several hundred thousand railroad grade crossings exist at the intersection of railways and roads in the United States alone. It is important to provide reliable and accurate warning signals of approaching trains to prevent accidents. Many of these crossings are instrumented with the conventional “crossbuck” warning bell and light mounted pole which are very expensive to build and maintain. However, over 100,000 grade crossings have no warning system.
There is an increasing concern with the number of accidents at railroad crossings. Collisions with trains are generally catastrophic, in that the destructive forces of a train are usually no match for any other type of vehicle. Indeed, federal and state regulations require that many types of vehicles, termed “priority vehicles”, take special precautions before crossing a “grade” railroad crossing. For example, school buses, hazardous cargo carriers and other emergency vehicles are often required to stop at railroad crossings and verify the absence of an oncoming train before proceeding. A “grade” railroad crossing is where a motor vehicle highway, street or road directly intersects a railroad track. An intersection of a highway and a train track that involves an overpass is not a “grade” crossing, as no collision would occur even if the vehicle and train arrived at the same location at the same time.
Thus, there is a need for a warning system in motor vehicles to alert drivers of approaching emergency vehicles, trains, rail road crossings, and school crossings. Many motorists simply do not hear horns or sirens as soon as they should which poses danger not only to themselves and passengers, but also to the emergency vehicles, trains, other passengers, and pedestrians.
There have been some solutions proposed to address this problem. One solution has been to use optical detectors at an intersection that detect light signals emitted from an approaching emergency vehicle, whereby the optical detectors would manipulate the traffic signal for oncoming traffic. One drawback to this solution is the lack of warning when an emergency vehicle is coming from behind a motor vehicle.
Another solution has been to use a radar detector, which would detect a signal transmitted from an emergency vehicle. One drawing to this solution is that false triggering of the radar may result in a driver turning off the radar detector out of frustration. Furthermore, the location and distance of the emergency vehicle would not be made available to the driver with this solution.
Yet another solution is to have the emergency vehicle transmit a radio frequency (RF) signal at a predetermined frequency or frequency range. In this case, each motor vehicle would be equipped with an RF receiver which would receive the RF signal output by the emergency vehicle when the emergency vehicle is traveling to its destination. A further enhancement to this solution would be to utilize global positioning satellites (GPS) in order to provide information as to the location of the emergency vehicle relative to the motor vehicle, whereby that information would be used by a microcontroller in order to determine the location of the emergency vehicle with respect to the driver's vehicle. The emergency vehicle's location would be displayed at the motor vehicle by way of one of four indicator lamps that are in the driver's view area (e.g., on the dashboard). Actuation of a first lamp would indicate that the emergency vehicle was somewhere ahead of the driver's vehicle, actuation of a second lamp would indicate that the emergency vehicle was somewhere to the left of the drivers vehicle, actuation of a third lamp would indicate that the emergency vehicle was somewhere to the right of the driver's vehicle, and actuation of a fourth lamp would indicate that the emergency vehicle was somewhere behind the driver's vehicle.
U.S. Pat. No. 6,339,382, issued to Donald Arbinger et al., discloses using both GPS signals, a RF transmitter, and a RF receiver. However, the '382 does not provide the driver with precise information as to the exact location of the emergency vehicle, and so the driver may not choose the best streets to travel through in order to evade the emergency vehicle and to evade the snarled traffic that typically occurs on streets that the emergency vehicle travels on.
The safety at railroad crossings has become of such significance that new federal agencies and studies have been undertaken to improve the grade crossing safety procedures. In view that a substantial number of fatalities occur every year due to collisions with trains, there has been an increased endeavor to provide sensors and detectors to warn oncoming traffic of the proximity of an approaching train. U.S. Pat. No. 5,739,768 describes a train proximity detector that provides a sensory indication to an operator when the vehicle and the train are located proximate each other. The train proximity detector of such patent receives the unique frequency transmitted by the train from the head end to the last car thereof. The carrier frequency transmitted by the train is decoded to identify certain data in the frame of transmitted data to thereby verify that the transmission originated from a train. While the train proximity detector functions very efficiently for its intended purpose, the operator of the vehicle will be given a warning of the proximity of the train, even if the train and vehicle are not on a collision course. For example, if the train and the car are traveling together, but in parallel paths, and there is no intersection between the road and the railroad track, the operator of the vehicle is nevertheless warned about the proximity of the train.
Other suggested devices attempt to overcome this problem, but at the expense of additional complexity, cost and apparatus that is required to be added to the equipment of the train. For example, in U.S. Pat. No. 4,942,395, by Ferrari, the train transmits on a first frequency to a receiver located at an intersection, and a second frequency is transmitted from a transmitter at the crossing to oncoming vehicles. In this manner, the vehicles do not directly receive the train transmission, and the vehicles are only provided a warning when in the proximate vicinity of the railroad crossing.
U.S. Pat. No. 5,554,928 by Shirkey et al. discloses a wireless train proximity alert system in which both a locomotive and vehicle rely on GPS coordinates for proper operation. In this system, the locomotive computes the train speed based on the GPS coordinates and transmits the coordinates and the train speed to a grade crossing transceiver. The grade crossing transceiver receives such information and computes an estimated time of arrival of the train. When the estimated time of arrival is within about 20-30 seconds of the grade crossing, the grade crossing transceiver transmits the coordinates of both the crossing and a boundary warning zone. A receiver mounted in a vehicle receives the coordinates of the grade crossing as well as the coordinates of the boundary warning zone around the grade crossing. In addition, the vehicle itself has a GPS receiver for receiving the coordinates of the vehicle. A controller determines if the vehicle is then within the boundary of the warning zone. If so, the controller determines if the vehicle is within a predetermined range of the crossing and if so, an alarm signal is provided. The predetermined range calculated by the vehicle controller is dependent upon vehicle speed and the braking distance of the vehicle which is a function of the type of vehicle.
Many other types of vehicle and train proximity detectors are proposed in the prior art. Many of the proposed techniques involve complicated and expensive equipment that must be added either to the train or to the vehicle, or both. It can be appreciated that in order for train proximity detectors to be installed on vehicles, in general, the equipment must be efficient, reliable and cost effective.
From the foregoing, it can be seen that a need exists for an improved train proximity detector that utilizes currently available resources to provide an operator of a vehicle with a sensory indication when the vehicle is in the vicinity of the train, and on a collision course therewith. Another need exists for an improved train proximity detector that relies on the presence of a train by conventional transmissions therefrom, as well as relies on GPS data for determining the location and direction of travel of the vehicle, whereby when such data is processed, it can be determined whether the vehicle is on a collision course with the train. A subsidiary need exists for a train proximity detector that has available data identifying each grade railroad crossing and corresponding compass bearing data of the roads crossing the railroad track.
Ideally, an automobile emergency vehicle warning display system should provide a motorist with visual and auditory warnings that an emergency vehicle is approaching and yet would operate reliably and be manufactured at a modest expense. Thus, a need exists for a reliable automobile emergency vehicle warning display system to avoid the above-mentioned problems.